ActiveRecord example

01 - generate_user_model.rb

⇥ rails generate model user
      invoke  active_record
      create    db/migrate/20110703115918_create_users.rb
      create    app/models/user.rb
      invoke    test_unit
      create      test/unit/user_test.rb
      create      test/fixtures/users.yml

02 - user_model_empty_migration.rb

class CreateUsers < ActiveRecord::Migration
  def self.up
    create_table :users do |t|

      t.timestamps
    end
  end

  def self.down
    drop_table :users
  end
end

03 - user_model_full_migration.rb

class CreateUsers < ActiveRecord::Migration
  def self.up
    create_table :users do |t|
      t.string :login,      :null => false
      t.string :password,   :null => false
      
      t.boolean :active,    :default => false
      
      t.timestamps
    end
  end

  def self.down
    drop_table :users
  end
end

04 - user_model_migration_result.rb

==  CreateUsers: migrating ====================================================
-- create_table(:users)
   -> 0.0107s
==  CreateUsers: migrated (0.0109s) ===========================================

05 - rails_console_work.rb

>> User.new
=> #<User id: nil, login: nil, password: nil, active: false, created_at: nil, updated_at: nil>
>> user = User.new(:login => "Vasya", :password => "password")
=> #<User id: nil, login: "Vasya", password: "password", active: false, created_at: nil, updated_at: nil>
>> user.new_record?
=> true
>> user.login_changed?
=> true
>> user.save
  SQL (0.4ms)   SELECT name
 FROM sqlite_master
 WHERE type = 'table' AND NOT name = 'sqlite_sequence'

  AREL (0.4ms)  INSERT INTO "users" ("login", "password", "active", "created_at", "updated_at") VALUES ('Vasya', 'password', 'f', '2011-07-03 12:16:40.408914', '2011-07-03 12:16:40.408914')
=> true
>> 

06 - rails_console_work-2.rb

>> User.find_by_login("Vasya")
  User Load (0.3ms)  SELECT "users".* FROM "users" WHERE "users"."login" = 'Vasya' LIMIT 1
=> #<User id: 1, login: "Vasya", password: "password", active: false, created_at: "2011-07-03 12:16:40", updated_at: "2011-07-03 12:16:40">
>> User.all
  User Load (0.4ms)  SELECT "users".* FROM "users"
=> [#<User id: 1, login: "Vasya", password: "password", active: false, created_at: "2011-07-03 12:16:40", updated_at: "2011-07-03 12:16:40">]
>> User.first
  User Load (0.4ms)  SELECT "users".* FROM "users" LIMIT 1
=> #<User id: 1, login: "Vasya", password: "password", active: false, created_at: "2011-07-03 12:16:40", updated_at: "2011-07-03 12:16:40">
>> User.find_by_login_and_password("Vasya", "password")
  User Load (0.4ms)  SELECT "users".* FROM "users" WHERE "users"."login" = 'Vasya' AND "users"."password" = 'password' LIMIT 1
=> #<User id: 1, login: "Vasya", password: "password", active: false, created_at: "2011-07-03 12:16:40", updated_at: "2011-07-03 12:16:40">
>>